Various types of sensing systems have been incorporated in shoes, insoles, socks and garments for monitoring various physiological parameters for various applications, including recreational, sporting, military, diagnostic and medical applications. Medical applications for sensing pressure, temperature and the like for purposes of monitoring neuropathic and other degenerative conditions with the goal of alerting an individual and/or medical service providers to sensed parameters that may indicate the worsening of a condition, lack of healing, and the like, have been proposed. Footwear-related sensing systems directed to providing sensory data for patients suffering from neuropathy, for gait analysis, rehabilitation assessment, shoe research, design and fitting, orthotic design and fitting, and the like, have been proposed.
Potential causes of peripheral neuropathy include diabetes, alcoholism, uremia, AIDS, tissue injury and nutritional deficiencies. Peripheral neuropathy is one of the most common complications of diabetes and results in wounds, ulcers, etc., which may be undetected and unsensed by the individual. There are 25 million diabetics in the US alone, with a projected population of 500 million diabetics worldwide by 2030. In the presence of neuropathy, diabetic patients often develop ulcers on the sole of the foot in areas of moderate or high pressure and shear, often resulting from walking during normal daily activities. About 70% of diabetics have measurable neuropathy, and every year about 5% of those patients get foot ulcers, and about 1% requires amputations. Foot ulcers are responsible for more hospitalizations than any other complication of diabetes and result in at least $40 billion in direct costs annually.
There is strong evidence that uncomplicated plantar ulcers can be healed in 6-8 weeks, yet current US clinical trials have reported a 76% treatment failure rate at 12 weeks. Many approaches to monitoring diabetic patients for the purpose of preventing ulceration from occurring, or to facilitate healing of existing ulcers, have been proposed, yet little or no improvement in ulceration or its complications has been observed. Off-loading may be an important aspect of ulcer prevention and healing. In “Practical guidelines on the management and prevention of the diabetic foot,” the authors concluded that mechanical off-loading is the cornerstone of treatment for ulcers with increased biomechanical stress. See, Diabetes Metab Res Rev 2008; 24(Suppl 1): S181-S187. It has been demonstrated that the offloading capacity of custom-made footwear for high-risk patients can be effectively improved and preserved using in-shoe plantar pressure analysis as guidance for footwear modification, which should reduce the risk of pressure-related diabetic foot ulcers. See, e.g., Diabet Med. 2012 December; 29(12):1542-9.
Sensing devices and footwear having sensors incorporated for monitoring pressure and other body parameters have been proposed. These devices have generally not been successful in preventing ulceration or accelerating healing of wounds, in part as a result of poor patient compliance. Notwithstanding the existence of several pressure sensing systems, the incidence of, patient pain and costs associated with diabetic ulcers has not declined. In one aspect, the components and assemblies for collection and analysis of data from sites such as feet and other body surfaces described herein are directed to providing intermittent or continuous monitoring and reporting of body conditions (such as pressure) at body locations for purposes of reducing the incidence and severity of ulcers and other wounds and accelerating the pace and quality of wound healing. In other aspects, sensors, interfaces, systems and materials described herein for collection and analysis of physiological and biomechanical data from sites such as feet and other body parts may be used for a variety of sports-related, military, fitness, diagnostic and therapeutic purposes.